Reacting to troubling economic news involving credit markets and large Wall Street players, U.S. Sen. Tom Harkin, D-Iowa, said he planned to propose making it illegal for CEOs of publicly traded businesses to simultaneously serve as chairmen of the companies’ boards of directors.

“I’ve often thought this is a classic case of conflict of interest when the CEO is also president and chairman of the board,” Harkin said on a conference call with reporters this morning. “They get to be chairman of the board and they hand-pick their board members. The board members give up their fiduciary responsibility to shareholders. So I think we’ve got to start separating that out.”